why expensive streamers

@12many 

The only Bluesound product I have is their Powernode, which drives my outdoor speakers on the deck; I’m using the internal DAC cuz it’s obviously about as far as you can get from a critical listening environment.  The Aurenders I’ve heard, because they’re ubiquitous these days, are all in dealer or show conditions, and have never been in A/B situations.  My A/B experience is among my current crop of streamers, which include a Raspberry Pi, an iFi Zen, a Pro-Ject Streambox S2 Ultra, and the streamer portion of my Gold Note DS10.  My experience is consistent with what the data and theory tell me, which is that I hear no difference between a $150 streamer and a $1000 streamer, with my DACs.  

At the high end, I spent an afternoon with a friend at a dealer comparing an Innuos Pulsar ($8000) to the streaming portion of a Simaudio 280D streaming dac ($3900), with a DCS dac.  No difference.  (This experiment was for my friend’s benefit, as he wanted to get comfortable with replacing his DCS with one of the new Simaudio North products - he chose the top of the line 891 - $25k!!)

All of this is consistent with the lab measurements that paul miller at hifi news has been doing on streamers.  I’ve put together a spreadsheet (sorry, I’m a recently retired finance guy) summarizing his results for a bunch of products, including Volumio Rivo (£1k), Aurender N200 (£7k), Melco N20 (£7k), Grimm MU1 (£10k), Aurender N30SA (£24k), and an Antipodes Oladra (£25k).  He compared the SNR and jitter results from these streamers in conjunction with 3 different DACs - AQ Dragonfly, iFi Neo iDSD, and a Mytek Brooklyn (i.e., from really cheap to moderate price, but nothing expensive).  His findings?  Jitter measurements for the $200 Dragonfly ranged from 105 psec to 150 psec, with the highest number coming from the Aurender N200.  Fear not though.  Remember, a psec = 1/1000 nsec, and the general rule is that we can’t detect jitter unless it’s about 30 nsec, which is 30,000 psec!

What about the iFi and the Mytek?  Even better jitter rejection, with ranges of 9-18 psec and 5-10 psec, respectively.  And the results on SNR tests were similar.  There, the only material noise issue was with the Dragonfly.  

In summary, the science, my experience, and actual measurements tell me the same thing.  A competent streamer should not be a source of audible noise; I am convinced that any differences we hear are either due to differences in signal processing (e.g., reclocking, up sampling, etc.), our DACs, or, yes, confirmation bias.  I also believe that most of the niche companies in the streamer space like to bundle their products - server, streamer, dac - because then it’s awfully difficult to pinpoint where that great sound you’re hearing is coming from.

I hope this is helpful.  I’d be happy to give a better, more comprehensive summary of the hifi news methodology, but in the interest of brevity (lol!!)….

@mdalton 

Like others, I cannot explain why you didn’t perceive differences. I already know you can explain why i do - you believe it confirmation bias. I have explored that in depth as I’m quite aware of that tendency in my own line of work so I try pretty hard to not fall into that trap and so I don’t think that is what’s happening. For instance, I’ve listened to a lot of quite pricey gear (amps, DACs, cables) in home which I’ve returned because even if I could perceive a difference - it wasn’t enough to merit opening my wallet. I’ve spent only when I felt it merited it.

I took my streamer (some would say high end - others mid range at >$5k) to my local dealer (who’s now looking to consider the brand). I first auditioned his Simaudio 680 DAC using their built in Mind2 module. Then we played the same track sourced from my streamer (via USB input on the DAC). He was surprised at how much better it was than the onboard module. I was actually hoping to sell my unit and reduce boxes. My bias (strong) was to favor the 680 as DAC w/ streamer. I came away disappointed and kept my streamer and went another direction w/ the DAC.

Yes, bits are bits. The data arrives fully intact. I will not dispute that. But the data is delivered in an analogue wave form with a slope to the rise and fall which affect when those 1 and 0s are registered (jitter). And, noise (not hiss) is carried along for the ride - affecting the same. 

Are differences night and day? Some would say yes. I would say no. But, for those of us pursuing higher performance, they were perceptible - and valuable. I perceive more spatial information (openness and depth as opposed to a flat soundstage). Tonally they are essentially the same. But, depth is significantly better w/ the better streamers. 

By the way, I had also auditioned the Bluesound Node 2i and Lumin mini streamers going into the Marantz reference player/DAC. I heard very little difference between those two unit against each other, and only minor differences between them and the Aurender N100H I owned at the time. Things have progressed since then and I’m comfortable w/ where I’ve spent - and not. I suspect others feel the same.

Perhaps you should ask one of the better companies out there to explain why there are differences. You might come away confident in your current position. Or, you might begin to wonder if you’re missing something. Let us know what you find.

@mgrif104 

you can’t attribute the differences to noise when objective measures of this most easy to measure quality show that’s not it.  that’s all i’ve been saying.  that’s like saying an engine puts out more horsepower when the data show us otherwise.  

@mdalton 

I didn’t attribute the difference to noise. I suggested that noise may be part of the equation. A subtle, but important difference. I did, however, suggest that the difference may be due to the rise and slope of the analogue waveform representing the 1s and 0s. A “bit perfect” file may be interpreted differently because of these minute variations.

Accordingly, I am skeptical of claims of certain DACs to be “immune” to jitter when the benefits of improved clocking are plainly audible. It turns out the ear is astonishingly sensitive to jitter distortions. Again, the benefits of femto second clocks are well known - and the results plainly audible to even not well trained ears. 

I would modify your metaphor thusly. Put poor quality fuel into any engine - regardless of the quality thereof, and see if it performs to spec.

You believe what you believe - and have provided some anecdotal evidence to support your claim - which I fully accept. I and some others believe differently and have provided anecdotal evidence to support our belief as well.

I would offer this. We’re still early in streaming relative to high performance audio history. We don’t currently know everything. It was originally postulated that CDs would provide “perfect sound forever” and that, because it was digital, all CD players (and transports particularly) would sound the same. That has been shown to be false, though perhaps still disputed by some who fail to do the work. 

Perhaps as an experiment you could try different inputs into your DAC. Try S/PDIF vs USB. Try different cable companies. They are all providing the same bit perfect stream, yet each will sound different. Those differences are measurable, though not necessarily quantifiable. They may not be massive differences, but they exist. This is because digital data is transmitted in an analogue wave form and cable geometry influences that transmission and introduces jitter.

If you struggle with this test - then let’s exaggerate it. Try an analogue RCA cable in lieu of a 75 ohm digital cable for your S/PDIF connection. It will likely sound thin and cast a steely glare over everything, all while transmitting a bit perfect file. Jitter.

Further, noise may not be primary, but it is an issue. All cables are antennas of some sort - both transmitter and receiver. Some are better insulated against this, but all are antennas of some sort. Computers tend to be noisy w/ EMF and RFI emissions from cheap power supplies and lots of other operating components not specific to audio. That’s why dedicated streamers with more attention placed on power supplies, etc. tend to outperform even high end computers. For instance, I had a souped up Mac mini dedicated as a streamer/server. 16 GB ram, solid state drives and everything not related to my music library turned off. That was its only function. It was handily outperformed by a modest streamer. Call me a fool or deluded if you wish. I wouldn’t go back to it.

In summary, the science, my experience, and actual measurements tell me the same thing.  A competent streamer should not be a source of audible noise; I am convinced that any differences we hear are either due to differences in signal processing (e.g., reclocking, up sampling, etc.), our DACs, or, yes, confirmation bias. 

@mdalton

you have tube gear, what does your science say about the sound profiles in different tubes? Care to show us some microphonic measurements?